Conveyer and heater therefor



9 11951 G. o. HOFFSTETTER CONVEYER AND HEATER THEREFOR 4 Sheets-Sheet 1 Filed Jan. 17, 1946 awe/Wm 6 flfi/faiezier w 4 5/. J \llllllAilllLm 4 l I I l l l I I l t u HHMWI IHH IH HIH HUM n IIIIIIIIIIIIIIIII Feb. 27, 1951 G. o. HOFFSTETTER CONVEYER AND HEATER THEREFOR 4 Sheets-Sheet 2 Filed Jan. 17, 1946 6 aff/ fsfe Zia?" 1951 G. o. HOFFSTETTER 2,543,287

CONVEYER AND HEATER THEREFOR I Filed Jan. 1'7, 1946 4 Sheets-Sheet 5 11 Ll W F 1951 G. o. HOFFSTETTER 2,543,287

CONVEYER AND HEATER THEREFOR Filed Jan. 1'7, 1946 4 Sheets-Sheet 4 zlvwamm ClQHof/siaiiar Patented Feb. 27, 1951 UNITED STATES- FATENT OFFICE .5 Claims.

This invention relates to hoppers, and :more particularly to :an improved means for heating the lower portion of the hopper including the material in the hopper and the conveyor which discharges the material from the hopper.

.An object of this invention is 'to provide in a hopper construction, particularly a hopper used with a material spreader such as lime, fertilizer or the like, or with a delivery hopper for delivering relatively fine material such as grain, coal or the like, a heating means whereby the mate rial which is conveyed along the bottom of the hopper will be held against freezing .in cold Weather, and the conveyor itself will be prevented from becoming jammed through freezing of the .moisture which may drip from the moist material.

Another object of this invention is to provide a construction of this kind which "may be used with either a belt conveyor, a screw conveyor 01' a chain or other suitable conveyor, for heating the conveyor and the material to prevent injury to the conveyor during freezing weather and to provide for the normal discharge of the material from the hopper during freezing weather.

With the foregoing and other objects in view, the invention will be more fully described hereinafter, and will be more particularly pointed out in the claims appended hereto.

In the drawings,

Figure l is a fragmentary transverse vertical section of a hopper having a material conveyor at the bottom thereof for discharging the material at one end of the hopper, and including a heating means constructed according to an embodiment of this invention. Figure 2 is a transverse sectional view, similar to Figure l, of a modification of this invention.

Figure 3 is a plan View, partly broken away, of the heating means embodied in Figure 2.

Figure 4 is a fragmentary vertical section of another modification of this invention.

Figure 5 is a fragmentary vertical section of a further modification of this invention.

Figure 11 is a fragmentary vertical section of 4':

a further modification of this invention.

Figure 12 is a fragmentary longitudinal section, partly in detail, of the structure shown in Figure 11.

'Il'. .An endless conveyor in the form of a belt 18 :is disposed :at the lower open ends of the walls i6 and ii and the conveyor I8 is disposed between a pair of depending lengthwise extending plates l9, having inwardly extending lower flanges 2B.

The conveyor it includes a chain 2-] secured to the inner side of the belt 18 and which is adapted to be trained over forward and rear pairs of sprockets (not shown).

In order to provide a means whereby the conveyor 18 may be heated so as to prevent freezing of moisture on the upper :and lower runs thereof, I have provided a heating chamber '22 which is formed between the upper and :lower runs of the conveyor 48. The chamber 22 is formed .by securing an upper elongated plate 23 between the depending plates t9 and positioning a lower plate 24 between the depending plates it spaced downwardly from the upper plate 23.

A pipe 25 is extended through one of the plates is adjacent one end of the hopper and preferably the forward end thereof, and the pipe 25 may be, as an example, connected to the exhaust pipe of an internal combustion engine for transmitting the hot exhaust gasses to the chamber 22. The heating medium is exhausted from the chamber 22 through an outlet pipe 26 connected to the opposite wall or plate H9 at the opposite end of the hopper from the intake pipe 25.

Referring now to Figures '2 and 3, there is disclosed a hopper 2i which is similar to the hopper '15 having an endless conveyor 28 'movably disposed at the lower spaced ends of the walls 29 and 3B of the hopper. The conveyor 28 is movably disposed between a pair of depending plates 3i having lower flanges 32 confronting each other, and in the present instance, the conveyor 28 is heated by means of a plurality of lengthwise extending pipes 33 disposed between the runs of the conveyor. The pipes 33 at their forward ends are connected to a transversely extended manifold '3 which has an inlet pipe 35 connected thereto, and the rear ends of the pipes 33 are connected to a rear manifold 36. The rear manifold 35 has an outlet pipe 31 connected therewith for exhausting the heating medium or providing a circulating means for circulating a heating medium through the pipes 33 and the manifolds '34 and 36. In the present instance,

the heating medium may, if desired, be water or other heated fluid, which may be circulated through the pipes 33 and the manifolds. An upper plate 38 is interposed between the pipes and the manifolds and the upper run of the conveyor 28 being secured at its opposite lengthwise edges to the side Walls 3! forming the support Referring to the drawings, and first to Figure and housing for the conveyor 28.

Referring now to Figure 4, there is disclosed a hopper 39 similar to the hopper i5, which has a conveyor 43 movably disposed between the lower spaced ends of the side walls ll and 42 thereof. The conveyor is movably mounted in a conveyor housing formed by depending side walls 53 and 44, and a lower wall 45. An inner wall 46 is secured between the side walls 43 and 44 below the upper run of the conveyor 40, and forms a heating chamber 41. An inlet pipe 43 is connected at one end to the side wall 44 and at the other end to a source of heating medium and an outlet or exhaust pipe 45 is connected at one end to the wall 33.

Refe ring now to Figures and 6, there is disclosed a hopper 56 formed of downwardly convergent walls 5i and 52 which are spaced apart at their lower ends. An endless conveyor 53 closes the opening formed by the lower ends of the side walls of the hopper, and the conveyor 53 has disposed at the opposite lengthwise edges thereof depending parallel plates E i and 55. The plate 5 has an inwardly extending flange 5'5 at its lower edge and the plate 55 has an inwardly extending flange 5? at its lower edge.

In order to pi'O' ide for heating of the conveyor 53, I have provided a pair of housings 58 and 59 on the outer sides of the walls 5 55, respectively. The housing 53 opens inwardly toward the wall opening or slot 66. A pair of plates 5% and 62 are'secured between the two plates or walls 5% and 55, thereby forming a connecting chamber G4. The housing 59 opens toward the wall 55 and the latter wall is formed with an opening 55. The two plates 6! and 82 are secured between the two openings and so that communication will be provided between the two housings 53 and 59 for not only h ating the walls 5 3 and 55 along the lengthwise edges of the conveyor 53, but also for heating the space between the upper and lower runs of the conveyor.

An inlet pipe Er; is connected at one end to the housing 59 and an outlet pipe is connected to the housing 58. A suitable heating medium may be circulated through the housings 59 and 53, passing from housing 55 through the chamber to the housing Referring now to Figures '1' and 8, there is disclosed a further modification of this invention, showing hop or 58 formed of downwardly convergent wal' An endless conveyor ll closes the hot. .n of the hopper 68 and is movably disposed letween a pair of depending walls or plates '52 and '53. A housing M, which is substantially U-Sha13d in transverse section, is secured to the wall it and a U-shaped housing '55 is secured to the'outer side of the wall l2. The two housings it and '55 are connected together at the forward end of the hopper by means of a connecting manif ld or pipe An inlet pipe i! is conne d to the housing i l at the forward end thereof, and outlet pipes and Z9 are connected to the housings i and adjacent the rear ends thereof. The heating medium is discharged into the housing and may then flow through the manifold ?6 to the housing 55 and may flow lengthwise of the housing l l.

Referring now to Figures 9 and 10, there is disclosed a further modification of this invention, wherein the hopper 86 has a screw conveyor 8! in the bottom thereof which is rotatable in a conveyor housing 82. A transversely U-shaped housing 83 is dependingly secured to the side walls 84 and 35 of the hopper, and is spaced from the which is formed with an elongated conveyor housing 82 so as to thereby form a heating chamber 88 about the housing 32. An inlet pipe 81 is connected to the forward end of the housing 83 and an outlet pipe 88 is connected to the rear portion of the housing 83.

Referring now to Figures 11 and 12, there is disclosed a further modification of this invention, including a hopper 89 having a screw conveyor 99 rotatably mounted in a conveyor housing 9!. In the present instance, the conveyor 90 includes a hollow shaft 92 which forms a heating chamber 93 centrally of the conveyor 90. The forward end of the hollow shaft 92 may have an intake pipe 94 connected thereto, the pipe 94 engaging in a gland 95 carried by the forward wall 95 of the hopper. The rear end of the shaft 92 may be opened to the atmosphere, if desired, for exhausting the heating medium such as exhaust gasses at the rear of the hopper.

With a. combined hopper conveyor and heating means as hereinbefore described, relatively moist material such as lime, coal, grain or the like, may be discharged from the hopper in freezing weathor without having the material freeze or clog the conveyor. It will be understood that the term conveyor as used in the description and claims includes an endless belt, a screw conveyor, a chain conveyor, cleats or the like.

What is claimed is:

1. In combination, a hopper, said hopper having longitudinal sides sloping downwardly and inwardly toward each other defining an elongated opening at the bottom thereof, a pair of spaced wals disposed dependingly, one from each sloping wall and ad acent said opening, a pair of vertically spaced horizontal walls extending between and connected to said depending side walls to define a heating chamber between themselves and said depending side walls, an endless belt conveyor at the bottom of said hopper having an upper and a bottom run thereof horizonta ly disposed respectively above and below said heating chamber.

2. In combination, a hopper, said hopper having longitudinal sides sloping downwardly and inwardly toward each other defining an elongated opening at the bottom thereof, a pair of side walls independent relation to said sloping walls with each one of said pair being spaced at opposite sides of said opening, two verticaly spaced horizontal walls extending between and connected to said dependent side walls to define a heating chamber between themselves and said dependent side walls, an endless belt conveyor having horizontally disposed top and bottom runs disposed at the bottom of said hopper, said top run being operatively movable between said eongated opening and said heating chamber with said bottom run disposed under and adjacent to said heating chamber.

3. In combination, a hopper, said hopper having longitudinal sides sloping downwardly and inwardly toward each other defining an elongated opening at the bottom thereof, a pair of spaced walls disposed dependingly, one from each sloping wall and adjacent said opening, a pair of vertically spaced horizontal walls extending between and connected to said depending side walls to define a heating chamber between themselves and said depending side walls, a horizontally disposed endless belt conveyor having vertically spaced top and bottom runs extending between said dependent side walls with said heating chamber disposed between said runs for heating both runs of the conveyor.

4. In a combined hopper and endless belt conveyor wherein the conveyor is disposed under the hopper, said hopper having longitudinal sides that slope downwardly and inwardly toward each other to define an elongated opening at the bottom of the hopper, a pair of vertical side walls dependently extending downwardly from said sloping walls with opposite ones of said vertical walls being spaced at opposite sides of said conveyor, said conveyor having a top horizontal run disposed adjacent said hopper opening and a bottom run disposed under said top run, a pair of vertically spaced horizontal walls extending between and connected to said depending side walls to define a heating chamber between themselves and said depending side walls, one of said horizontal walls being disposed adjacent said top run of the conveyor and the other horizontal wall being disposed adjacent the bottom run whereby a heat medium circulated in said chamber will heat both runs or" said conveyor.

5. In combination, a hopper, said hopper having a pair of ends spaced apart by longitudinal sides that slope downwardly and inwardly toward each other to define an elongated Opening at the bottom thereof, a pair of spaced walls disposed dependingly, one from each sloping wall and adjacent said opening, a pair of vertically spaced horizontal walls extending between and connected to said depending side walls to define a heat- REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 119,903 W'akelee Oct. 10, 1871 516,995 Williams Mar. 20, 1894 763,349 Armstrong June 28, 1904 888,257 Passburg May 19, 1908 1,329,407 Hogue Feb. 3, 1920' 2,215,964 Knowles Sept. 24, 1940 

